Comet Labs WN591 Manual de usuario Pagina 16
- Pagina / 49
- Tabla de contenidos
- MARCADORES
Valorado. / 5. Basado en revisión del cliente
Help! There is a comet in my computer! 13
3.4.1 And I measured my comet at 400× magnification...
While we are talking about lengths, scaling factors and related topics, let us discuss a
common misconception about “magnification”. We recorded an image of a comet and now
we want to publish it. For publication, we need to quote the scaling of the image. Let us
say that we observed the comets under the microscope, using a 40× objective and 10×
eyepieces. We looked at the comets under a microscope at 400× magnification, because the
laws of optics state that the final magnification of the image observed equals the product of
the magnification of the objective and the magnification of the eyepiece (40 × 10 = 400).
Then we recorded an image. Can we now write in the caption of the printed (published)
image “at 400× magnification”? No, because this is wrong. In a microscope, the optical
path that leads from the objective to the eyepieces is different to that from the objective to
the camera (Figure 2C). There may be several lenses of different magnification inserted in
the objective-camera optical path. A camera is mounted on a microscope with an adapter,
and the magnification of commonly used adapters are 0.63× or 1×. Hence, to describe the
scaling of an image, we need to insert a scale bar (Figure 7).
The same principle applies to writing the Materials and Methods section of scientific
publications. We can mention the magnification of the objective that we used (40×), but
not write “Images were recorded at 400× magnification”.
Figure 7. Scaling of a printed image. Printed images should contain a scale bar. This image was
recorded using a 40× objective, at the scaling factor of the original image 0.36 µm per pixel. In an
image editing program (e.g. Adobe Photoshop), we can add a scale bar to the original image,
which is exactly 56 pixels long to represent 20 µm (20 µm / 0.36 µm pixel
-1
= 56 pixels). We then
save the image containing the scale bar. Now, we can enlarge or shrink the size of the image - the
scale bar always represents the exact current magnification. If printed on A4 paper, the size of the
scale bar for the image on the left is 16 mm and for the one on the right 6.5 mm. Hence, in the
printed version, the left image is shown (printed) at magnification 800× and the right one at 325×
(16mm / 20 µm = 800; 6.5 mm / 20 µm = 325).
20
µ
m
20
µ
m
- Barbara Vilhar 1
- Contents 2
- Figures 3
- Do you have a problem? 4
- 1 Fluorescence microscopy 6
- (e.g. mercury lamp) 9
- (e.g. halogen lamp) 9
- 2 Detection of emitted light 10
- 3.1 Grey values 12
- 3.2 Segmentation 13
- 3.3 Geometric calibration 14
- Background 18
- Head Tail 18
- 3.5.3 Tail extent moment 20
- 3.5.4 Comet profile 21
- 3.5.5 Olive tail moment 22
- 4.1 Look-up table (LUT) 24
- (bright pixels) 30
- 5.3 Image saturation 33
- 5.5 Shading 38
- 5.8 Binning 43
- Dr Barbara Vilhar 49
Buyers LT12 Handbücher
Bedienungsanleitungen und Benutzerhandbücher für Für das Auto Buyers LT12.
Wir stellen 1 PDF-Handbücher Buyers LT12 zum kostenlosen herunterladen nach Dokumenttypen zur Verfügung Bedienungsanleitung
Comentarios a estos manuales